Radio transmitter control apparatus



Nov; 13, 1934. s HABERLE r AL 1,980,585

RADIO TRANSMITTER CONTROL APPARATUS Filed oct. 6, 1935 4 Sheets-Sheet 1Mam W M INVENTORJ BY f7...

ATTORNEY Nov. 13, 1934. s. D. HABERLE El AL RADIO TRANSMITTER CO NTROLAPPARATUS Filed Oct. 6, 1935 4 Sheets-Sheet 2 INVENTORS BY %A A ATTORNEY13, 1934- s. D. HABERLE ET AL RADIO TRANSMITTER CONTROL APPARATUS FiledOct. 6, 1933 4 Sheets-Sheet 3 I m L I Mala-Jaw ATTORNEY 1934- s. D.HABERLE El AL RADIO TRANSMITTER CONTROL APPARATUS Filed Oct. 6, 1953 4Sheets-Sheet 4 ATTORNEY Patented Nov. 13, 1934 UNETED 3,982,585 GFFH ERADIO TRAN SIVIITTER CONTROL APPARATUS of Massachusetts ApplicationOctober 6, 1933, Serial No. 692,364

2 Claims.

The invention relates to radio transmitters and with particularity to animproved apparatus for controlling the adjustment of tuning thereof.

An object of the invention is to provide an improved form of remotecontrol for a multirange radio transmitter.

A further object is to provide an improved remote control circuit for aradio transmitter whereby the anode and cathode potentials areautomatically applied in displaced time relation.

A feature of the invention relates to a remote control system for amultirange transmitter for selectively tuning the transmitter todifferent ranges, and for delaying the application of anode potentialuntil the automatic tuning operation has been completed.

A further feature relates to the combination of a panel type radiotransmitter having a plurality of separately adjustable electric units,together with a common drive mechanism and remote control means forselectively and automatically adjusting one or more of said unitssimultaneously.

A still further feature relates to the novel organization, arrangementand relative location of the parts which go to make up an eflicient andeasily adjusted remote-control" transmitter.

In the drawings, Fig. 1 is a side elevational view of a transmitterpane'lwith the side plates removed;

Fig. 2 is a detail top plan view of a portion of the tuning andselecting mechanism;

Fig. 3 is a detail elevational view of a portion of the tuning andselecting mechanism;

Fig; 1 is a front view of the'dial and adjustable contact mechanismshown in Figs. 1 and Fig. 5 is a schematic wiring diagram of theelectrical system used to control remotely the apparatus of Figs. 1 to4; and

Fig. 6 is a'schematic wiring diagram of a modification of the system ofFig. 5.

Referring more particularly to Fig. 1, there is shown a frameworkconsisting of vertical uprights 1 in the form of angle irons suitablyunited by horizontal angle bars 2 to 7. The front face of the frameworkcarries a suitable panel 8, preferably of sheet metal or, if desired, ofinsulating material, on which are supported the various tuning dialsdescribed below. Supported on the crossbars 2 to 6 are respectiveshelves dividing the framework into compartments, each compartmenthaving mounted therein tuning or adjusting units associated with acorresponding section of the transmitter. In the lowermost compartment 9is sit uated the common driving motor 10 and the associated powercontrol equipment. Compartment 11 may contain a variable condenser 12and associated apparatus for tuning one section of the transmitter, forexample, the antenna circuit. Compartment 13 may contain a variablecondenser 14 and associated apparatus for tuning a different section ofthe transmitter, for example, a feedback circuit. Com partment 15 maycontain a variometer 16 and associated apparatus for adjusting or'tuninga different section of the transmitter, for example, the plate ciicuitof the oscillator 2. Similarly, compartment 17 may contain a multi-taprotary switch 18 and associatedapparatus for tuning a still differentsection of the transmitter. the tuning units shown are merelyillustrative, and if desired, any other well-known forms of electricaltuning or adjusting elements having other circuit functions may beemployed. In any event, each of the devices 12, 14, 16, 18 comprises afixed and a movable member. For example, the condenser 12' consists ofthe usual stator plates and rotorplates, the latter being attached to arotatable shaft 19. Similarly, the rotor plates of condenser 14 areattached to a shaft 20. The rotor (not shown) of the variometer 16likewise is attached to shaft 21, while the rotor of the multi-ta-pswitch'l8 is attached to shaft 22. I

Motor 10 drives a main vertical shaft 23 through suitable reductiongearing 24 and shaft 23 is in turn coupled through reduction gearing 25and clutch 26 to shaft 19. Similarly, shaft 20 is coupled to shaft 23through the r e duction gearing 27 and clutch 2B; shaft 21 is coupled toshaft 23 through .reduction gearing 29 and clutch 30; and shaft 22 iscoupled to shaft 23 through reduction gearing 31 and 32. As shown moreclearly in Figs. 2 and 3, each clutch, e. g., clutch 26, comprises adisc 33 of non-magnetic material which is fastened to the associatedshaft 19, and supported on disc 33 is another disc 34 of iron or othermagnetic material. Disc 34 is preferably attached to disc 33 by a leafspring 35 in such a manner that itv is incapable of rotation withrespect to disc 33, but is capable of slight bodily displacementlongitudinally of shaft 19.

Mounted for rotation about shaft 19 is a sleeve 36 which carries at itsright-hand end a gear 37 in mesh with an associated gear 38 on shaft 23.Sleeve 36 carries at its left-hand end a disc 39 of non-magneticmaterial. As shown in the drawings shaft 19 is provided with suitablebear ings in bearing brackets 39 and 40.

Fixedly mounted on opposite sides of the shaft 19 are electromagnets 41,42, which when energized cause disc 34 to be positively coupled to thecontinuously rotating disc 39, it being understood that when the-magnets are deenergized,

It will be understood, of course, that there is a slight gap between thediscs 34 and,

39, as shown in the drawings. Fastened to shaft 19 is a disc 43 ofinsulating material which carries a combined contact arm and detent 44.Shaft 19 extends outwardly through the panel plate 8 and carries apointer 45 which is adapted to register with a suitably marked scale 46on the front of the panel to indicate the angular position of shaft 19and contact arm 44. Preferably also, a manually operable knob 47 isprovided and is coupled through suitable gearing (not shown), so thatshaft 19 and its associated tuning unit may be rotated manuallyindependently of motor 10. Associated with each dial is an arcuate slot48 in the panel 8 and adjustably mounted in the slot 48 are a series ofcontact carriers. As shownmore clearly in Figs. 2 and 3, each of thesecarriers comprises two members 49 and 50 which are coupled together by afastening screw 51 Member 49 carries an arm 52 which terminates in aV-shaped recess in which is mounted a suitable contact face 53. Thecontact carriers maybe located at any desired points in the slot 48corresponding to the desired selective position of the associated tuningunit. By 'riiea'ns ofthe screw 51 members 49 and 50 may be loosened andmoved to any desired position, and then screw 51 may be tightened tofasten the contact carrier in selective position. It will be understood,of course, that while the drawings show two contact carriers for eachdial, a greater. or less number may be employed, dependent upon thenumber of selective positions desired, i. e., dependent upon the numberof wave lengths to which the transmitter is to be tuned. It is obvious,of course, that if the panel 8 is of metal as above described, thecontact carriers will be insulatingly mounted therein. -.The contact arm44 terminates at its upper end in a V-shaped contact shoe 54.and isadapted to enter each of the V-shaped notches 53 in succession as theshaf 19 rotates. Thearrangement is preferably such that when member 54engages a contact 53, suitable circuits are closed to deenergizeelectromagnets 41, 42, and the members 53 and 54 also act as'a detent toretain the shaft 19' in its selected position. As will be describedbelow, the desired contacts 53 are electrically marked under control ofsuitable electrical circuits, and since the shaft 23 is continuouslyrotating, the tuning shafts 19, 20, 21, 22 also continue to rotate untilthe associated contact arms 44 engage the selectively marked members 53.

Referring to .Fig. 5, a description will now be given of a preferredform of "electric circuit for remotely controlling the various tuningdevices 12, 14, 16 and 18. In-Fig. 5,parts corresponding to those inFigs. 1 to 4 are schematically shown and bear the same designationnumerals. For the purpose of remotely controlling the adjustment of thevarious tuning units there are provided two manually operableswitches 55and 56 on a suitable remote control panel 57. Instead of operating theswitches 55 and 56 manually at the remote control point, these switchesmay be located, if desired, at the transmitter panel and operated by asuitable selective mechanism such as step-by-step Strowger switches froma remote point. Each of the switches 55 and 56 is provided with a set offixed contacts, each contact corresponding to one of the wave lengths towhich the set is to be tuned. It will be assumed for the purpose ofexplanation that each of the tuning units of the transmitter is adaptedto be tuned to four separate wave lengths, in which event there will beprovided with each dial 45 (Figs. 1 to 4), four contact carriers 56. Itis well known that in ordinary radio transmitters the various tuning oradjustable circuit units must be moved to different angular positions,depending upon their function in the ci cuit. For this reason thecontact carriers for each dial are separately mounted for manualadjustment. For example, if it is desired to tune the transmitter to 100meters, the first con tact carrier 50 of the set associated with theshaft 19 will be positioned at one point previously determined. Thefirst contact carrier 50 of the set associated with shaft 20 willlikewise be positioned at a previously determined point, which may ormay not be the same, angularly speaking, as that of the first-mentionedcarrier. Likewise, the remaining fixed contact carriers of the setsassociated with shafts 21 and 22 will be adjusted manually to theirpredetermined positions at which the transmitter is to transmit at 100meters. 7

Assuming for the purpose of explanation that the transmitter is to betuned to its second lowest wave length, that is to say, the secondcontact carrier 50 of each set is to be selectively marked. Under thisassumption the switches 55 and 56 will be manually or remotelypositioned on the second off-normal contact. In this position, a circuitis closed from the power main 58 through the switch 55, thence inparallel through relays 59 and 60, to the power main 61. Relay 59 whenenergized, closes its contacts and completes a circuit from thealternating current mains 53, 61 in parallel, to the primary windings62, 63 of transformer 64. Transformer 64 is provided with a secondarywinding 65 for heating the cathodes 66, 67 of suitable rectifier tubes68, 69. A high potential secondary winding 76 provided on transformer 64is connected in full wave arrangement with the anodes of the rectifiers68, 69, thus providing a direct.- current supply for the wires '11, 72.When relay 60 operates as above described, it in turn operates relay 73.Relay 73 when operated connects the current supply wires 74 to the wires75 which supply heating current to the filaments or cathodes of thevarious tubes (not shown) in the transmitter. The wire 76 which controlsthe high potential current for the anodes of the various tubes is, onlypartially connected in .circuit through one of the contacts of relay 73and through the various safety contacts 77, 78, 79.-

The contacts 77, 78, 79 may,'for example, be

controlled by doors or other parts of the trans-' mitter so that whenthese doors are open for inspection, the high potential supply isdisconnected.

Coincident with the operation of relays 59, 60, there is closed acircuit from the main 58, switch 55, wire 80, contact 81 of relay 82,wire 83, thence in parallel through the windings of relays 84, 85 andconductor 86, to the main 61. Relay 84 when operated, completes thecircuit from the three-phase mains 87 to the motor 10, which ispreferably of the three-phase type. Relay 85 when operated opens thecircuit over the conductor 76, thus preventing the application of highpotential to the anodes of the various transmitter tubes until all thetuning units are automatically adjusted to their selected positions, aswill be described. At this time also a circuit is traceable from thepositive conductor 71 through the inner back contact of clutchcontrolrelay 88, thence through the winding of the clutch magnet 89(corresponding to magnets 41, 42 of Fig. 2), thence to the negativeconductor 72. A similar circuit is traceable from the positive conductor71, through the inner back contacts of clutch control relays 90, 91, 92,to energize the associated clutch magnets 93, 94, 95. It will beunderstood that the magnets 93, 94, 95 correspond to electromagnets 41,42, associated with the respective clutches 38, 30, 32 (Fig. 1). Theenergization of the magnets 89, 93, 94, 95 causes the rotatable elementsof the associated tuning units to be coupled to the common drive shaft23 which is driven by motor 10. It is to be noted that in the drawingsall elements having a common drive are interconnected by dot-dash lines.Consequently, each of the clutch magnets being energized, causes each ofthe associated switch arms 44*, 44 44, 44 to rotate, if these respectivecontact arms are not in the proper position. Since it was assumed thatthe remote control switch 56 was positioned on the second contact, thena circuit is traceable at this time from the negative conductor 72,switch 56, wire 96, switch marking relay 97", to the positive conductor71. Relay 97 in turn closes a circuit from the negative conductor 72through its front contact 98 and thus electrically marks the secondcontact associated with each of the switch arms 44*, 44 44, 44 It willbe understood that the switch contacts associated with the arms 44 to 44are schematically indicated in Fig. 5 and represent the contact carriers50 (Figs. 2, 3 and 4). Arms 44 to 44 therefore rotate clockwise untilthey engage their associated second contacts. Assuming that arm 44engages its second contact before any of the remaining contact armsengage their second contacts, then a circuit may be traced from thenegative conductor 72, front contacts 98* contact 99, arm 44, clutchcontrol relay 88, thence to the positive conductor 71. Relay 88 uponbeing operated, opens the abovedescribed circuit for the clutch magnet89 and thus the tuning unit 12 becomes stationary in the selectedposition. The remaining arms 44*, 44 44 continue to rotate until theycontact with their respective marked contacts. Upon their engagementwith these contacts the respective clutch magnets 93, 94, 95 aredeenergized as already described for the magnet 89, thus causing thetuning units 14, 16, 18 to remain stationary in their adjustedpositions. When all of the clutch-control relays 88, 90, 91, 92 areoperated, a circuit is closed from the negative conductor 72 through thewinding of relay 82, thence through the outer front contacts of relays92, 91, 90, 88 in series, to the positive conductor 71. Relay 82 whenoperated, opens its contact 81, thus causing the release of relays 84and 85. Relay 84 upon restoring to normal, breaks the circuit for motor10, while relay 85 in restoring to normal, completes the circuit overconductor 76 and thus enables high potential to be applied to the anodesof the various tubes in the transmitter.

There is thus provided an arrangement whereby each of the tuning unitsmay be operated individually and separately by remote means to differentangular positions with respect to the remaining units, and means arealso provided whereby the application of anode potential is delayeduntil all the tuning operations are complate. It will be understood, ofcourse, that the shafts carrying the arms 44 to 44 are mounted for 360rotation, in which event the motor 10 is of the nonreversible type. Itis believed that the manner in which the tuning units may be selectivelyoperated to the other positions than those assumed will be obvious fromthe foregoing description. In each case all the clutch magnets aresimultaneously energized from the remote point to initiate the tuningoperation, and may be selectively deenergized in non-simultaneous order,depending on the relative angular positions of the various contactsassociated with switch arms 44 to 44*.

Referring to Fig. 6, there is shown a modified form of electricalcircuit for achieving the remote control. This embodiment differs fromthat of Fig. 5 merely in that the rotatable tuning circuit elements aredesigned for forward and reverse rotation through approximately only180, whereas in the embodiment of Fig. 5 they are designed for rotationthrough 360, always in the same direction. In general, the circuits ofFig. 6 are the same, and function the same, as those already describedin connection with Fig. 5, and accordingly parts of Fig. 6 correspondingto those of Fig. 5 bear the same designation numerals. In addition tothe apparatus of Fig. 5, Fig. 6 employs a set of reverse-controlcommutators 101, 102, 103, 104, there being one commutator for each ofthe tuning units and clutch magnets 89, 93, 94 and 95, respectively. Acommon limit or reversing switch 105 is also provided for controllingthe direction of rotation of the reversing three-phase motor 10. Inaddition, a reversing relay 107 is provided for reversing the polarityof two of the three-phase wires from the mains 87 to the motor 10.

For purposes of explanation let it be assumed that the transmitter hasbeen previously left with the movable arms 40 40, 49, 40 on the secondcontact sets shown, and also let it be assumed that the transmitter isnow to be adjusted. remotely to bring the said arms to the first contactsets. At the remote control panel 57, the switches 55 and 56 will be seton the contacts as shown in the drawings, causing the relays 59, 60 and73 to operate as above described, and resulting in the application of D.C. to the wires 71 and 72 through rectifiers 68 and 69. A circuit maynow be traced from the positive conductor 71, inner back contact ofrelay 88, winding of clutch magnet 89, commutator segment 101 brush 101,to the negative wire 72. Magnet 89 being thus energized, couples thetuning unit 12 to the main shaft 23 (Figs. 1 to 4). Relays 84 and 85 areat this time operated as above described under control of relay 82.Relay 85 prevents the high potential conductor 76 being connectedthrough to the anodes of the various tubes which, however, have theirfilaments lighted under control of relay 73. Under these conditionsrelays 107 and 108 are normal and it will be assumed that the mains 87are connected through the back contacts of the relay 107 so as tooperate the motor 10 in a clockwise direction. It will also beunderstood that at the time magnet 89 was energized, the remainingmagnets 93, 94, 95 were likewise energized through the back contacts oftheir associated relays 90, 91, 92, respectively. Consequently, all thetuning units being coupled to the motor 10, are simultaneously rotatedand at the same time arms 40*, 40', 40, 40 are likewise rotated in aclockwise direction. Relay 97 is energized through switch 56 as abovedescribed, but the negative wire 72 is not connected to the firstcontacts associated with the arm 40, since the armature of relay 9"! isconnected to said conductor '72 through the outer right contacts ofrelay 107 which are now open. Arms 40 to 40 and brushes 101 to 104therefore continue to rotate in a clockwise direction until the saidbrushes 101 to 104 disengage their respective commutator strips 101 to104. Just before this disengagement the arm 105 engages contact 109,resulting in the operation of relays 108 and 110 over the followingcircuit: terminal 58, switch 55, conductor 80, contacts of relay 82,conductor 83, conductor 111, thence in parallel through the windings ofrelays 108 and 110, conductor 112, arm 105, contact 109, conductor 113,conductor 86, terminal 61. Relay 110 in operating short-circuits theclutch control commutators and thus maintains the energizing circuitsfor the clutch magnets 89, 93, 94, 95. Relay 108 in operating completesthe energizing circuit for relay 107 which reverses the polarity to twowindings of the motor 10, resulting in a reversal of direction of themotor rotation. As schematically shown in the drawings, the contacts 109and 114 are preferably long enough to maintain the relays 108 and 110operated during the short interval required for the reengagement of thearms 101 to 104 with their respective commutator strips on the reversemotion. The various tuning units continue to rotate in acounter-clockwise direction until the arms 40 to 40 engage thepreviously positioned first contact sets. This engagement may or may notbe simultaneous, depending on the previously adjusted positions of therespective contacts, and while the drawings show the contacts associatedwith the contacts 40 to 40 in relatively equal angular positions, itwill be understood that this is merely illustrative, since the positionof these contacts will be previously determined by the angular positionsof the tuning units necessary to tune or adjust the various circuitelements to the proper points for a given frequency. Let it be assumedthat the arm 40 on the counter-clockwise rotation is the first to engagethe first contact of its associated set. Under these conditions acircuit may be traced from the negative wire '72, conductor 115,conductor 116, outermost contacts of relay 10'7, conductor 11?, contacts98 arm 40 relay 83, to the positive wire Z1. Relay 88 in operatingbreaks the circuit for the clutch magnet 89 and thus stops the tuningunit 12 in its selected position. At this point it should be noted thatthe relay 108 is preferably of the ratchet link type, that is, it staysin its last operated position, so that when it is energized as abovedescribed, its contacts remain closed, even though its coil isdeenergized. However, when the coil of relay 108 is again energized, theratchet opens the contacts which remain open until the relay is againenergized. Under the above conditions, therefore, the relay 108 has itscontacts still closed, thus maintaining the counter-clockwise rotationof the motor 10. As each of the remaining arms 40, 40, 40 engages theelectrically marked first contacts, the associated clutch control relays90, 91, 92 are operated, resulting in the deenergization of theassociated clutches 93, 94, 95 and the stopping of the associated tuningunits in their selected positions. With the relays 88, 90, 91, 92energized, a circuit is completed through the outermost contactsthereof, through the winding of relay 82 which operates, and by means ofits contacts 81, the latter relay opens the circuit for the motorcontrol relay 84, thus bringing the motor to rest. It is clear,therefore, that the clutch control commutators 101 to 104 as well as theselective switch arms 40 to 40 will continue to rotate until all thetuning units have been properly positioned. This may require one or moreadditional reversals of rotation of the motor, depending upon therespective previously adjusted angular positions of the contactsassociated with the arms 40 to 40 At the same time that relay 84 isdeenergized as above described, relay 85 is likewise deenergized andcompletes the plate interlock circuit to the transmitter by completingthe connection from conductor 76 through the various safety interlockcontacts '77, '78, 79, through the contacts of relay 85, thus insuringthat the anode potential is applied to the transmitter tubes only afterall the automatic tuning and selective operations have been fullycompleted. The transmitter is now in condition to be controlled by theremote telegraph key or microphone for the transmission of telegraph,voice-modulated signals, or any other type of radio transmission.

It will be understood, of course, that the broad features of theinvention are not limited to the remote adjustment of circuit units fora transmitter, but are equally well suited to adjustment of a receiverwhere such receiver comprises independently adjustable units such, forexample, as the tuning units and the feedback units of a regenerativereceiver or the like.

What is claimed is:

1. In combination, a radio set, means controlling the application ofcathode heating current to said set, means for controlling theapplication of anode current to said set, a plurality of separatelyadjustable tuning units for said set, a motor for driving said units, aplurality of clutches one for each of said units, means for remotelycontrolling the simultaneous energization of said clutches, means torender said heating current control means effective to apply heatingcurrent to the cathodes of the radio set upon the energization of saidclutches, means for efiecting the selective deenergization of saidclutches, and means to prevent the application of said anode currentuntil all said clutches have been selectively deenergized.

2. In combination, a radio set, means to control the application ofcathode current to said set, means to control the application of anodecurrent to said set, a plurality of separately adjustable tuning unitsin said set, a motor for T driving said units, clutches between saidmotor and each of said units, a clutch control relay for each clutch,remote means for effecting the simultaneous energization of saidclutches through said control relays and for simultaneously controllingthe application of the cathode heating current, and means for preventingthe application of the anode current until all the said clutches havebeen selectively deenergized. SUMNER D. HABERLE. ROBERT J. DAVIS.

